Lathe-chuck



C. H. REID.

LATHB GHUGK Patented 'J une 5, 1883.

UNITED STATES PATENT OFFICE.'

CHAR-LES H. REID, OF DANBURY, ASSIGNOR TO R. H. BROVN 8s OO., OF I NEV HAVEN, CONNECTICUT.

LATH -CHUCK.

SPECIFICATION forming part of Letters Patent No. 279,017, dated J'une 5, 1883. Application filed January 23, 1883. (No model.)

To all whom. it may concern.

Be it known that I, CHARLEs H. REID, of Danbury, in the county of Fairfield and State of Connecticut, have invented new and useful Improvements in Lathe Chucks 5 and I do hereby declare that the following is a full and accurate description of the same.

v This invention relates to the chuck for which Letters Patent No. 226, 246 were granted to me 1o April 6, 1880 and it consists in changing the structure of the double or right and left screw, so that the bearing-shoulders for the same are between the adjacent ends of said screws, instead of at their distant ends, as in saidpatent, whereby several important advantages are secured, viz zfrst, the cells or seats for the screwsl may be bored full size from the outside ofthe chuck, second, the separation of the screws at the center of the chuck permits o the insertion ot' a larger body between the jaws tha-n would otherwise be possible 5 third, the screws maintain alonger engagement with the jaws, and therefore permit them to open wide 5 fourth the screw will keep cleaner than heretofore,because,the end being exposed, the

dirt can work out of the thread freely.

That others may fully understand my invvention, I will particularlyT describe it, having reference to the accompanying drawings,

Figure l is a transverse horizontal sectional view of my improved chuck. Fig. 2 is a vertical section view.

Inr the accompanying drawings, A is vthe cylindrical body or bed of the chuck, which has a smaller cylindrical extension, A. The extension A is longitudinally cored out or perforated to afford means of attachment to the spindle of the lathe. The body or bed A is 4o channeledtransverselyto receive thelaterally adjustable jaws B B, which are grooved on each side to receive the guide-tongues or tenons c upon the bed A, as shown, Fig. 2. The bed A is constructed witha recess, A, which is parallel to the transverse channel. The recess receives the shaft D, which is provided with right and left screw-threads g g, and projecting head, to which a wrench may be applied for turning it, as shown. The threads upon the two sections of this shaft 'D are at 5o different inclinations and operate in opposite directions, so as to open or close the jaws B B simultaneously. The screws g g do not approach close together, as in my patent above named, but are separated a distance on the 5 5 shaft which, at the central point, is less in diameter than the screw-thread, and therefore offers less obstruction to the entrance between the jaws, as shown at q. To properly accommodate this central part of the shaft D,the re- 6o cess A2 is made smaller-,at the middle, and the larger portion of it, at each side of this central part, forms shoulders s, against which the ad-A jacent ends of the screws g g bear when in action. The recess AZ may therefore be eX- 6 5 tended'full size to the exterior surface of the chuck, and may be formed by boring in full size from the outside to the shoulders s-an opA eration of much easier character than the enlargement of the central' part, as required in 7o.

my patent above named. The screws g g `may therefore extend to or beyond t-he exterior surface of the chuck, and will have a correspondingly longer engagement with the jaws, and said jaws may therefore separate farther than 7 5 before without diminishing the hold of the screw. The projection of the ends of screws also affords facility for the escape of dirt or other obstructing matter, which could not so freely escape before.

Having described my improvement, what I claim as new isl. The head A, having atransverse channel and also a recess,A`, with central shoulders,s, formed in it, combined with the shaft D, having the right and left hand screws g f/ thereon, fitted to bear against said shoulders, and the jaws B B', adapted to be moved by said screws, substantially as set forth.

2. The head A, provided with a transverse 9o channel, and also with a cylindrical recess, A2,

parallel with and communicating with saidl channel, and provided with the shoulders s s near its center, combined with the jaws B B, each fitted to slide in said channel, and provided with a screw-thread cutin one side, and the shaft D,eXtended full size to the exterior surface ofthe head A, and provided with the screw-threads g g to engage with the correcenter, combined with jaws B B, adapted to spending screw-threads of said jaws, snhstannieve radially in said channel, and the shaft tially as set forth. D, Wholly outside the Vplane of said jaws, so as 3. The jaws B l3,having arectilinear motion not to encroach upon the open center, and the 15 in the ysaine plane, but in opposite directions, screws g g,xed to thc ends of said shaftout` and the shaft D,having fixed upon 1t the operside the shoulders s .#,substantiall'xlv as set forth. ative screw-threads combined with the head A, provided with the central abutting shoulders, CEAS' H' REID s, substantially as set forth. "it'nessesz 1o 4. The head A,havingatransverse channel, ALLAN W. PIGE,

and also a recess, A, with shoulders s near its DAYID B. BOOTH. 

